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Friday, February 24, 2017

More DSB, from Belgium and Spain

Frank ON6UU writes:

Hello Soldermelters,
Maybe some interesting news for you as there are some new kits at hand from EA3GCY (
I’ve made the MFT-40 DSB without any problem,  all parts were provided with the kit,  only things to buy were a microphone connector,  a speaker and an antenna plug.   The box was taken from my attic and was a VGA-selector in his previous life.
Kit came together in a few evenings,  I followed the very well written manual,  all was well pointed out,  which resulted in a working kit.  After aligning the kit I could start making qso’s.   The microphone was made from a piece of tube,  a simple switch and a electret microphone,  it doesn’t look pretty but the microphone works.
Rx-Tx 7.066 – 7.133  (With DDS the complete 7MHz band)
Pwr :  some 3W peak.
Double Side Band
Made some You-tube films about it.  
Easy to make,  no SMD,  easy alignment without necessity of expensive material.   Fine for someone who never made a transceiver,  hence the name...My First Transceiver,  MFT.   As soon as the weather permits I will take the TRX out in the field and activate a SOTA with it.
Now working on the MFT-20 DSB.   I’m hoping for an 80mtr version to come available too.  :-)
All info is on Javier’s site. (
72, 73
Keep the solder melting !!

Thursday, February 23, 2017

Walter KA4KXX's "Al Fresco" Oz DSB rig with VFO Mod

A while back we ran a post about the MDT 40 DSB rig out of Australia. Walter KA4KXX liked the design so much that he built his own version and, with it, made his first homebrew phone contacts. I always say that DSB is a great way to break into the world of microphones.  Walter is obviously on the right path -- not only did he come up with a nice Al Fresco DSB rig, but he modified the VFO to get additional coverage and to incorporate a frequency counter.  FB Walter!

Walter KA4KXX writes:

Since I earned my Ham Radio license in about 1979, I have always operated only on CW since I like to build all my own equipment, but recently at the SolderSmoke website I discovered the MDT 40 Meter DSB Transceiver, and decided this was the design I had always been looking for to finally build and operate on phone.

After I made my first phone contact after only 5 minutes of trying, just a few weeks ago, I was so excited I sent an email thanking designer Leon of

Then I modified the VFO further to cover the entire 40 meter USA General Class License phone band, which is 7.175 – 7.300, in two overlapping steps.  I also added a 5K fine frequency adjustment, used a more friendly 1SV149 Varactor diode which I purchased on EBay at very low cost, and also added a high impedance buffer (found at the website listed below) to the VFO to drive a frequency counter.

I was able to implement these modifications very easily since I always make my own un-crowded state-by-stage Manhattan style circuit boards and build first on a breadboard.
So far I am very pleased with the results.

Walter KA4KXX

Tuesday, February 21, 2017

HB2HB: Contact on 40 meters with W0PWE

I got on 40SSB this evening and called CQ with my BITX DIGI-Tia.  Hooray!  Jerry W0PWE answered me with HIS 40 Meter DIGI-TIA.  His is still Al Fresco style.  Very nice.  We add this to the homebrew to homebrew scorecard.  Thanks Jerry!

Jerry's rig:

Monday, February 20, 2017

VU2XE's BITX40 (with a cool CAD box)

A year or so ago Pete and I encouraged Kiran VU2XE to try the BITX.  He followed through, on our suggestion and went a step further, using CAD to design a box for the BITX.  I will try to post a link to Kiran's CAD files on the BITXHACKS blog.  

Kiran writes:

Hi Bill and Pete,
It is almost year since you seeded idea about the BITX. I am still a listener of your podcast.
After finishing my RF amplifier project late last year, I was thinking of few projects and BITX was on the top of the list. I ordered and received a very beautiful BITX40 kit with Arduino, I got it recently. I also designed a simple case for it using CAD software. It can be used by anyone -- just go to your local laser/CNC shop to get it cut in Aluminum.  I just thought of sharing the excitement with you.  This rig and it sounds awesomely good :)

Attached are some snaps and design files (I am no expert in CAD etc. it is my first attempt to learn and build)

Happy projects and 73s
Kiran VU2XE 

Saturday, February 18, 2017

Peter Parker VK3YE on Vintage Gear (in his new book!)

Homebrew Hero Peter Parker has a new book on the market.   I was really taken by his description of the joys of restoring older gear.  Peter really nails it.   Here is an excerpt:

Vintage Equipment
     The collection, restoration and use of historical equipment is another movement in amateur radio.  The musty smell of warming dust, the heavy clunk of rotary switches and the velvet smoothness of precision tuning drives are joys of every use.
     Such sensuality is absent from modern plastic-fronted, wobbly-knobbed transceivers.  Old rig cabinets felt they had something in them.  A kick would hurt you more than them.  And etched panel markings confirmed they were built to last.
    Unlike today’s dainty push buttons with stunted travel and disembodied beep, toggle switches showed you where they stood.  Weight, life and play made adjusting controls for nulls and peaks (as often required) both a pleasure and occasional frustration.  Even if only as mechanical backlash on a bad tuning dial, it was as if the equipment was telling you something, like a ridden horse does through its reins.  Not like newer gear’s lack of tactility which is like a ‘dead fish’ handshake, all take and no give.
    There are psychic as well as physical joys.  The thrill of bringing neglected or dead equipment to life drives many.  It’s an underestimated skill.  You start with nothing and almost anything done represents progress when building from scratch.  Whereas with a repair it is very easy to render something that’s 80% good completely useless with a careless drop or slip.

More about ‘Getting back into Amateur Radio’ is at 
& the video at
Designer: Douglas Bowman | Dimodifikasi oleh Abdul Munir Original Posting Rounders 3 Column